Method of making a tooth brush



se a. 13, was. 1 2,130,244

METHOD OF MAKING A TOOTH BRUSH Filed March 18, 1936 INVENTOR TUP ZEI Ni'ihil] m lli ATTORNEY Patented Sept. 13, 1938 UNITED STATES PATENT OFFlCE 2 Claims.

This invention relates to a tooth brush, and more particularly to a bamboo tooth brush of the type in which bunches of bristles are inserted in groups of holes in the bamboo and are anchored 5. therein by means of metal clips.

One object of the present invention is to prvide an improved bamboo tooth brush having improved sheet metal clips for anchoring the bristles in such manner that the brushes may be sterilized and the bristles are effectively and permanently retained in place.

Another object of my invention is to provide an improved bristle anchoring clip consisting of a sheet metal stamping having protruding portions adapted to form shallow grooves in the sides of the bristle receiving hole, and a further object is to provide the clip with one or more portions of reduced dimensions to permit bending or twisting of the clip to resist withdrawal from the said hole in the bamboo brush head.

Still another object of my invention is to provide an improved method of anchoring the bristles in the head.

With these and other objects in view, my in- Vention consists in the novel construction and arrangement of parts and in the method hereinafter described with reference to the accompanying drawing, and. particularly pointed out in the appended claims, it being understood that various changes in the form and proportions of the parts may be made without departing from the spirit of the invention or sacrificing any of the advantages thereof.

In the drawing Fig. 1 is an enlarged side view of a bamboo tooth brush with a portion thereof in sections; Fig. 2 is an enlarged view showing one of the holes in the head of the tooth brush; Fig. 3 is an enlarged section showing one form of my improved clip in position to grip the bristles in the head of the brush; Figs. 4, 5 and 6 show three slightly modified forms of my improved clip, and Figs. '7 and 8 are views showing one form of the improved clip, Fig. '7 indicating the position of the clip while being introduced, and Fig. 8 showing the final position.

Referring to the drawing, the head H] of the bamboo tooth brush is integral with the stem or handle ll, being formed from a strip of bamboo with the hard natural outer skin of the bamboo forming one face-preferably the back or outer face l2 of the brush. Suitable holes or recesses l3 are bored or formed in the head Ill and the bunches of bristles M are introduced into these holes l3 after being doubled over the retaining clips l5, Fig. 1.

My improved clip is formed from rustless sheet metal and consists of a small stamping. In the form shown at Fig. 4 of the drawing, the clip I5 has a body part I'6 with two similar side arms H, the total width of the clip being slightly greater 5 than the diameter of the hole as indicated by the dot and dash lines [8 at this figure, so that when theclip is inserted in the hole with the bristles folded over the body l6 between the arms I1 the side extremities I9 of the clip form two shallow l0 diametrically opposite grooves 2!, Fig. 2 in the comparatively soft wood of the bamboo brush head, and this clip is made with parts 20 at the base of the arms I! of reduced dimension so that the arms l-l may bend and/or twist inwardly as 15 shown at Fig. 3 when the clip is pressed into the base of the hole, and the central part of the body I6 is also of reduced dimensions so that this part may also be bent in such manner that the protruding parts 19 of the clip are moved out of 20 alignment with the grooves 2| formed in the bamboo so that withdrawal of the clip is prevented.

Referring to Fig. 5 of the drawing the clip here shown is stamped from thin sheet metal preferably of a suitable rust-proof alloy and is shaped 25 to provide side portions 22 that extend into the Walls of the hole l8, these parts 22 being tapered towards the leading edge of the clip as it is advanced into the hole with the bristles folded over the curved edge 23. The clip shown at Fig. 6 30 of the drawing is somewhat similar in construction, but the lower edge 24 of the clip shown at Fig: 5 is curved while the lower edge 25 of the clip shown at Fig. 6 is straight, and in both clips the mid-portion forms a waist 26, Fig. 5, and 21, Fig. 35 6, of reduced dimensions so that the clips may be bent or distorted when they are forced into the extremities of the holes so that the protruding side parts 22 are not in alignment with the grooves 2| formed in the sides of the holes during 40 the introduction of the clips, and withdrawal is thus prevented.

In the diagrammatic views Figs. '7 and 8, Fig. '7 shows the position of one of the improved clips (such as the clip shown at Fig. 5) as it is intro- 45 duced into the hole 29, and Fig. 8 shows the position of the same clip after it has been forced into its final position and is bent, tilted, distorted or displaced in such manner that the grooves 2| formed in the sides of the hole by the introduc- 50 tion of the clip are incapable of permitting the withdrawal of the clip and bristles.

The clip is so constructed as to embrace the bristles and consists of thin sheet metal adapted to be distorted as soon as the clip reaches its 55 The clip will not only be bent inwardly, but will also be bent out of its original plane by buckling over. The engagement of the inner end of the bore with the end of the clip causes the clip to buckle, since the clip is relatively thin in cross section, and relatively broad in elevation. Note in Fig. 3 that the effective thickness of he clip is a greater when it is distorted upon reaching the lower end of the bore than the thickness of the grooves which it has formed in the upper portion of the bore. Withdrawal of the clip is thus prevented, since the protruding edges are no longer free to slide freely through the grooves formed in the walls of the bore during the introduction.

In all the preferred forms of the improved clip the leading extremities are adapted to bite into the bamboo at the'extremity of the hole, and when pressure is applied by the implement used, in the known manner, in the introduction of the clip and bristles, the-clip is caused to tilt and/or bend in such manner that withdrawal of the bristles and clip is efiectively prevented.

My invention also consists in the improved method of anchoring bristles in the head of a bamboo tooth brush which method comprises mounting the bristles upon a clip having protruding side edges that groove the sides of the hole as the bristles are introduced, forcing the clip carrying the bristles into the hole by means of a suitable implement and imparting a slight twisting or turning movement to the implement when the clip is moved into its final position so that the protruding edges of the clip are prevented from alignment with the grooves formed in the walls of the hole with the result that the bristles and clip are permanently anchored in place in the head of the brush.

Although the drawing and the above specification disclose the best modes in which I have contemplated embodying myinvention, I desire to be in'no way limited to the exact details of such disclosure for in the further practical application oimy invention changes in the dimensions and detail construction may be made as circumstances require or experience suggests without departing from the spirit of the invention within the scope of the appended claims.

What 'I claim is:

1. A method of planting bunches of bristles in bores formed in the head of a bamboo tooth brush, which comprises mounting the bunches of bristles upon retaining clips, forcing the clips into the bores while the side edges of the clipsform diametrically opposed grooves in the walls of the bores, and displacing and distorting the clips out of the plane of the grooves at the extremities of the bores so that the said edges are moved from alignment with said grooves to prevent withdrawal of the side edges of the clips through said grooves.

2. A method of planting bunches of bristles in a bore formed-in the head of abamboo tooth 1 brush, which comprises mounting a bunch of bristles upon a clip, forcing the clip into the bore in such manner that the edges of the clipform grooves in the walls of the bore, and displacing the clip out of the plane of the grooves so that the edges are moved from alignmentwith the grooves, at the extremity of the bore, so as to prevent withdrawalof the clip through the said grooves in the bore.

TORAZO NISHIO; 

